The World Wide Web is a collection of servers connected to the Internet that utilize the Hypertext Transfer Protocol ("HTTP"). HTTP is a known application protocol that provides users with access to documents (e.g., web pages at a web site) written in a standard mark-up page description language known as Hypertext Markup Language ("HTML"). HTTP is used to transmit HTML web pages between a remote computer (e.g., a server) and a client computer in a form that is understandable to browser software (e.g., Netscape Navigator.TM., available from Netscape Communications Corporation of Mountain View, California) executing on the client computer.
A web site can be customized to a specific user of a client computer (hereinafter "client") when information about that client is available to the site. For example, if a web site has access to a record indicating that a client is a sports fan, then the site may be specially configured to display a sports advertisement whenever that client accesses the site. Such functionality can encourage sports sponsors for the web site, consequently increasing site revenue.
To that end, the World Wide Web utilizes "cookies" to provide client information to a web site. As is known in the art, a cookie is a data block that is transmitted to a client browser by a web site. Upon receipt, the browser stores the cookie in a given manner such as, for example, in a text file called "cookie.txt." The cookie is transmitted back to the web site each time the browser requests access to a web page from the web site.
Among other things, cookies commonly include data identifying the client requesting access. When used in this manner, such data may be utilized to access a database at the web site to ascertain relatively large quantities of data about the client. Since the World Wide Web includes many interconnected servers, many databases can have the same information relating to a single client. The art has responded to this unnecessary information duplication by locating information on shared central computer systems that may be accessed by two or more web sites. More particularly, whenever accessed by a client, any one of several web sites can access a single database on a shared central computer system to obtain stored information (if any) relating to the client. Information thus is shared by each web site that has access to the registration system.
One known method of implementing a shared central computer system as described above requires that the central computer system web site upload a cookie to a client while the client is accessing one of the member web sites (i.e., while the client is in the member web site domain). One such system is the DOUBLE CLICK NETWORK.TM. system, available from DoubleClick Inc., of New York, N.Y. This type of system is ineffective, however, if a browser is configured to receive cookies from no other domains other than the domain in which the browser is currently accessing. For example, when accessing a web site in a domain "site.com", a browser configured to receive cookies from no more than one domain cannot receive cookies from a domain "registration.com." Use of a browser configured in such a manner undesirably eliminates the functionality of such a centralized client information system.